In recent years, more and more electronic devices such as tablet personal computers and portable digital assistants include touchscreens to improve operability and usability. A user can enter information on a position on a display surface of the liquid crystal panel by touching the display surface of the liquid crystal panel with a finger or a stylus. According to this configuration, the user can perform intuitive operation, that is, the user can perform operation with direct feeling as if he or she directly touches an image displayed on the liquid crystal panel. A display panel including such a position inputting function of the touchscreen is disclosed in Patent Document 1.
Patent Document 1 discloses a liquid crystal display device that includes an integrated touchscreen. The liquid crystal display device includes pixel electrodes and common electrodes that generate electrical fields for driving liquid crystals. The common electrodes are used for position detection. Capacitances between the common electrodes and detection electrodes may be different depending on whether or not an obstacle to interrupt the electric fields is present. Whether or not touching operation is performed is determined based on whether a difference in capacitance is present.